TRANSACTIONS OF MICROSCOPICAL SOCIETY. 
DESCRIPTION OF PLATE IV., 
Illustrating Professor Henfrey's paper on some Fresh-water Con- 
fer void Algae, new to Britain. 
Figs. 1 — 25, Pandorina Morum, Ehr. 
Fig. 
1 — Perfect form, with 16 gonidia, side view. 
2. — Ditto, polar view. 
3. — Perfect form, witli 32 gonidia, side view. 
4. — Ditto, polar view. 
5. — A gonidium, side view. 
6. — Ditto, from above. 
7 and 8. — Side and end view of a small frond, with 16 gonidia. 
9. — Side view of a small frond, with 32 gonidia. 
10. — A frond, with the gonidia dividing. 
] 1. — A more advanced frond. 
12. — A frond, with the young ones nearly perfect. 
13 and 14. — Young fronds free. 
15 to 20. — Side and end views of fronds, with the gonidia pushed close 
together. 
21. — Side of a frond, like fig. 15, with the gonidia encysted, their contents 
turned red, and the gelatinous envelope nearly dissolved. 
22. — End view of the same. 
23. — Side view of one with 32 gonidia, more magnified. 
24. — Eesting-spores (encysted gonidia) free. 
25. — One more magnified, to show the membranous coat. 
Figs. 26 and 27, Apiocystis Brauniana, Nageli. 
26. — A half-grown frond. 
27. — Green gonidia from the interior, the lower ones dividing. 
Figs. 28 — 36, Clathrocystis ceruginosa, Henfrey. 
28 to 31. — Successive stages of development of a frond. 
32 to 34. — Fragments of a broken-up frond, like fig. 31. 
35. — Green cells from the interior of the gelatinous fronds, some under- 
going division. 
36. — One more magnified, to show the membranous coat. 
